Originally Posted by
MikeFromMKE
Do you have any evidence to support that? While it wouldn't surprise me it is hard to say one way or the other without numbers. It is a nice perk for the elites though, and since they didn't remove any seats it really isn't costing them any money other than the installation costs. It would surprise me to see them raise prices almost across the board if they were getting little uptake because you would assume raising the price would drive more people away.
If you look at seat maps, a few hours prior to scheduled departure, you can get a fairly good picture (no pun intended).

The aircraft looks lopsided, with the first four rows sparsely filled, while the rear 80% or so is densely occupied. It's not very scientific, but there is a pattern. If customers
are upgrading to STRETCH for a fee, they could be doing it at the airport, at the last minute, therefore, not showing up on seat maps a few hours before departure.
I think there is better take on the Airbus, for some reason; maybe it's the 3x3 seating that makes STRETCH more desirable, especially on long haul flights.